I've got an upcoming trip to San Antonio planned and am thinking of taking my 5d2, 24-105, 70-200 and flash in a crumpler 6mdh. I only want to take (2) lenses because with a bad back I can only heft the bag for short times. I'd like some input based on my gear list if this is the best two lens combo of the lenses I have. This is going to be a two week trip via Amtrak from Los Angeles. I will be touring around the San Antonio area and also heading up to the Austin area. This will be the first time I've used my gear away from my home area, thanks.